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HYDRO - PNEUMATIC SYSTEM 



OF 



SEWERAGE. 



BY 



URBAN H. BROUGHTON, Assoc. M. Inst. C. E 




THE SANITARY ENGINEER PRESS, ©2 4 64 FULTOK ST* ( N. Y. 



THE SHONE 



HYDRO -PNEUMATIC SYSTEM 



OF 



SEWERAGE. 



BY 



URBAN H. BROUGHTON, Assoc. M. Inst. C. E. 



1 



! 



, 



.1 



THE SHON 









lv Urban H. Broughton, Assoc. M. Inst. C. } 



T 



advantages derived from a perfect system of sewerage are so 
manifest that it is unnecessary to enlarge upon them, "salus popul 
suprema lex." It therefore behoves all municipal and other author- 
ities, about to execute sewerage works, to fully inquire as to wl r 
those works, when executed, will provesanitary or unsanitary. If the lat- 
ter, theA nnot fail to serious! affect the physical health, and coi 
quently t ioral well being and material prosperity of the communit) 
1 ferring to the water-carried sewerag system, which is general! 
admitted to be the only practical method for large cities, Professor 
Huxley, R ..inanaddn- livered at the Society \rt wyears 

ago, stated: "Disagreeable and imperfect as the old ct pool S) m \ s, 
it was attended with very little danger as compared uath that which 

, the modem water-sewage system, if this stem is imp. 

I, ,, perfect, then it is very perfect ; and in fact it is thi >nly possibl 

m in great cities at the present day. It has, however, this terrible 
peculiarity that if it is imperfect, it becomes the most admirable ma- 
mcrv for distributing the death and disease which maybe found in 
one locality, as widely as possible into others, and into tfa houses 

of the people That I believe to be as absolutely true a statement 
any to be and in the records of science of the pr< nt da) ml it then 
fore mes a question, how are we to see that this ter-sev 

ratus is .. tl 1 may call reasonably perfect ? Of course, no human 
arrangements are really perfect. There must be an element of chain 
introduced into all our arrangements, but it is within our power that 
the element of chance is kept within reasonable bounds." 

By the Shone" system a reasonably perfect system ot sewerage is 
, tined,because by it engineers can invariably work by rule, and it is 



4 



therefore worthy of full consideration at the hands of sanitary engineers 

and others. 

Whatever differences of opinion may in time past have been enter- 
tained as to the advisability of a duplicate system of sewers, one for 
rainfall, and the other for sewage, the advocates for the combined sys- 
tem are now in a minority, and though adaptable to both the " combined 
and the « separate "systems, it is to the " separate" system that the Shone 
system can be most advantageously applied in its entirety. 1 his sys- 
tem has now been applied to several large towns and districts (referred 
to hereafter) in England and abroad, and the results have amply justi- 
fied the inventor's claims, both as to the scientific principles upon which 
it is based, its efficiency, and the economy of first and annual charges. 
In the earlv part of last year a select committee of the House of Com- 
mons, presided over by Sir Henry Roscoe, F. R. S, was appointed to 
inquire into the ventilation and drainage of the House, and the result of 
the investigations of the committee, led to the Shone System of Sewerage 
being applied to the British Imperial Houses of Parliament. This can- 
not but be considered as a national acknowledgment of the superiority 

of the Shone system. 

The great desiderata in a system of sewerage are that— 

ist. It should remove effectually, and rapidly, the sewage from the 
inhabited area to some given point. 

2 d. The sewage should be removed at the velocity requisite to 
cleanse the channels. 

3 d. It should be applicable to any area, whatever the natural con- 
figuration may be. 

4th. If the sewage is delivered upon land, it should be delivered 
fresh before it has lost its chief manurial properties. 

5 th. If the sewage is discharged into the sea, or river, the dis- 
charge should take place at all times, regardless of the state of the tide. 

6th. The cost of construction and annual maintenance should not 

be excessive. 

7th. It should be capable of being extended, as a town grows, with- 
out altering any work already constructed. 

It is the writer's object to show how the Shone system complies 
with these desiderata j but before entering into details he cannot do 
better than give here a brief description of the principle of the shone 
system in the words of Mr. W. Donaldson, M. A., Mem. Inst. ('. E., 
who was Engineer in charge of the Reading sewerage and sewage-farm 
works, which are now regarded as a sanitary and financial success. 



s 

"By the adoption of this principle, good gradients can always be 
obtained, whatever may be the natural configuration of the surface of 
the inhabited area. Only small self-cleansing stoneware pipes are there- 
fore required, which cost very little, and in a sanitary point of view are 

by far the best. 

" This result can only be obtained by the adoption of several col- 
lecting stations, at which the sewage can be raised from a lower to a 
higher level. With the ordinary appliances for pumping, this system 
would be impracticable. The first cost of construction of buildings and 
machinery would be very great, and also the subsequent annual working 
expenses, because the cost of labor and several other items would be 
the same at each station, and the cost of fuel much more than if all the 
power required was brought into use at one place. By the invention 
of the * Shone Hydro-pneumatic System ' and ' ejectors/ this difficulty can 
be overcome. The ejector is an apparatus for raising liquid by means 
of compressed air, which can be conveyed in pipes to almost any distance 
without sensible loss of pressure, if mains of a proper size are adopted. 
Compared with mains for the conveyance of water, the mains required 
for the conveyance of an equal bulk of compressed air, in the same time, 
are very small, because the loss of pressure due to friction is, in the 
case of air, ceteris paribus, only about one-thirtieth at the most of the 
loss due to the same cause in the case of water. 

"In the case of ordinary pumping apparatus a great difficulty is 
always experienced in securing sites for the erection of the machinery. 
The machinery itself occupies a considerable space, and tanks of large 
capacity are required, because the rate of pumping is uniform, whilst 
the rate of flow of the sewage is variable. 

" The ejector stations will be all underground, and may be erected 
in the public thoroughfares, without interfering in any way with the 
street traffic. Unless, therefore, special reasons exist for the erection of 
stations on private property, no expense need be incurred m procuring 
sites. No collecting-tanks are required, because the rate of working of 
the ejectors will vary with the rate of supply of the sewage. A suffi- 
cient number of the ejectors must be provided at each station to deal 
as fast as it comes, with the maximum quantity. When the flow of 
sewage diminishes, the rate of working will diminish. By a very sim- 
ple automatic arrangement of the machinery for producing compressed 
air, the rate of production of compressed air varies with the quantity 

required by the ejectors." 

It is generally admitted by sanitary engineers, and therefore may 
be looked" upon as an axiom, that the velocity at which sewage should 
be madeto flow through house-drains, should never be lessthan three feet 



6 



per second, and in public sewers, when the greatest quantity of sewage 
is flowing through them by gravitation, the velocity should never be less 
than from 2 to ȣ feet per second. If provision is made for obtaining 
these velocities, the sewers become self-cleansing sanitary sewers; if not, 
they will soon become sewers of deposit, and resemble more or less 
ebngated cesspools, the noxious and death-bearing gases from which 
are exuded into the atmosphere, through manholes, gratings, and venti- 
lators It is therefore of paramount importance that sewers should be 
laid at gradients which will cause them to be self-cleansing, and conse- 
quently sanitary ones. Why, then, is this not done ? The answer is, that 
in the majority of cases, from the natural configuration of the area it is 
not practical to do so when the system of gravitation is employed, as 

will be explained in detail. 

Some areas are favorably configurated for gravitation sewers, and 
in these cases artificial means for the propulsion ot sewage are 
unnecessary ; but in the majority of cases, the natural configurat.on 
is such that to collect and convey the sewage sanitarily to one point, 
there to be raised or discharged, as the case maybe, is practically impos- 
sible, because, in order to lay the pipes at gradients in accordance with 
hydraulic rules, so as to give the requisite velocity to make them self- 
cleansing, thev would have to be laid at a great depth, involving a cost 
which would' preclude their being so laid. Engineers, therefore, in 
designing works on the old gravitation system, are compelled, by the 
nature of the em itself, 10 ignore hydraulic rules, and put in sewers 
which cannot be sanitary sewage-carriers. Artificial flushing arrange- 
nents, superadded to an extensive system of non-self-cleansing sewers, 
will not avail the engineer in producing a sanitary sewerage system, 
and maintaining it permanently as such. 

Now, upon the Shone system the area under treatment d d 
into as many natural drainage areas as is desirable, and the sewage f. d 
each conveyed in small pipes laid at proper gradients to the lo* | >Oim 
Here here is an ejector station, and the sewage, as fast as it flows inl- 
and fills an ejector, is raised automatically by compressed air. into d 
iron main, and com ed under pressure to the outfall, and it is th foi 
impossible that the sewage can ever remain long enough in the s< wei 
d ompose and give off noxious gases. Mon over, howevi c long U may 

remain in the s I pipe, it will not decompose, because it is cut oil from 
the dec imposing tit— the air. The sealed iron main can be laid, li 
water-pip et ily under the surface of tl round, what* ei 

the natural coni iiration ma] be, inasmucl as suf lent pr< »ur< is 
always pr 1 to dein the - age at the utfall in a rapid manner, 



7 

and once in the sealed main it can have no communication with the 
atmosphere except at the outfall. 

Quite as important as the gradient of a sewer, is that it should be 
proportioned to the volume that it has to deal with. Large sewers, pro- 
vided they are properly charged with sewage, can be laid at compar- 
atively flat gradients ; on the other hand, small sewers must be laid at 
comparatively steep gradients, but even at these gradients they must be 
properly charged, as the maximum velocity is obtained when a pipe is 
running about three-fourths full, which is a little in excess of that when 
running one-half full, or full. In the two latter cases it is the same. 

One great blot on the "combined " system is, that sewers must be 
designed to carry the maximum amount of sewage, subsoil- water, and rain- 
fall, that can possibly occur. Now as this maximum amount occurs but 
seldom, at other periods there is not sufficient volume flowing through 
them,even supposing they are laid at proper gradients,to render them self- 
cleansing, and therefore they may be considered during normal periods 
to be most unsatisfactory. 

;/ The primary essentials of good drainage necessary to make sewers 
sanitary ones are : (i) Gradients laid in accordance with hydraulic 
rules ; (2) sewers proportioned to the volume they have to carry ; and 
(3) acertain volume to flow over a proper gradient. And here the writer 
would point out the difficulties which beset an engineer, in designing a 
system of ordinary gravitation sewers in an unfavorable area. He can 
exercise his skill in obtaining the best gradients possible, and he can 
calculate the sizes necessary to convey the assigned volume of sewage, 
but his skill will not give him control over the velocity. If the gradients 
are flat, the sewers become cesspools, and breeders of sewer-gas. The 
control over the gradients can therefore only be obtained by making the 
network of sewers converge to the natural drainage point, instead of to 
one outfall only. On the ordinary system, this would mean several inde- 
pendent pumping-stations, with separate staff to each station, instead of 
merely an automatic ejector, worked (together with all other ejector 
stations) from one air-compressing station, which may be any distance 

away. . . 

In the Shone system the length of sewers leading to each ejector 

station is short, so that the sewage is delivered quite fresh, and in such 

condition passed into the sealed iron main, and delivered at the outfall, 

when if it is to be used for manurial purposes, it has a much greater value 

than if delivered in a stale or half -decomposed state; and to insure the small 

main-sewers supplying the pneumatic ejectors with sewage being swept 

clean as it were, twice a day, automatic flush-tanks (on the same 

principle as the House Sewage Ejector, described hereafter) 



8 

supplied with clean water, are to be placed, where necessary, at the head 
of the small properly-laid main sewers converging at the ejector 
stations. All the gravitation sewers leading sewage into the ejectors 
would be effectively ventilated, but being always free from foul sewage 
the air-currents flowing through them would be harmless and innoc- 
uous. 

Again, by the ordinary system, pumping goes on at a uniform rate 

during a certain portion of the 24 hours, but as the rate of flow of sew- 
age is variable, storage must be provided equivalent to certainly more 
than one-fourth of the whole day's flow. Not unfrequently the sewers 
themselves are designed to act as storage-re-crvoirs, with the inevitable 
effect of generating sewer-gas. The rate of working the ejectors varies 
with the rate of flow of the sewage, so to prevent waste of power, gov- 
ernors and reducing-valves are frequently used to stop the steam-supply 
to the compressors, when the pressure required to raise the sewage 
has been obtained. The compressors, therefore, as well the ejectors 

work automatically. 

In the Shone system the air-mains and air-recei vers,filled with pure air, 
discharge the same functions as storage-reservoirs filled with foul, decom- 
posing sewage. In the case of the storage of air, unsanitary conditions 
are avoided, whereas in the case of the storage of sewage, unsanitary 
conditions are assisted. If a city adopts the Shone system in its entiretx 
it does net require larger than 7-inch gravitation collecting sewers, and 
these should be laid at a gradient of 1 in 200. The excavations required 
will be small. Rainfall or subsoil (if needed) pipes can be laid in the 
same trench, when convenient s also can the sealed iron main and air- 
pipes. When circumstances will permit, an ordinary gravitation sewer 
may take the place of the sealed iron main. 

In sewering a city in the ordinary method, the probable iture 
inc ase in population must betaken into consideration, in designing 
main sewers, but in the Shone system it is not necessary, in the ime 
way, to take the future growth of a < y into consideration, as an\ 
increase in the population can be provided for when it arises, by putting 
down additional ejectors as they are required. 

With reference to house-drains, notwithstanding their lar^- 1 
cities to discharge s* age, if they do not exce d 4 to 6 incl 5 in 
diameter, and if they are laid at the gradient suitable for them, it is 
found that they perform their functions tolerably successfully; but when 
the hous Irani is very Ion even though it should be laid at the [ l- 

dient suitable to its size, which is rarely thi in flat or low in 

plaa the plan of letting the sewage into it in < r- ing dribh 
cannot fail, • or later, to render it foul and obj ble. I h 



\ 



9 

only way to overcome this difficulty, is to cause the whole sewage dis- 
charges of the house, as these accumulate, to pass quickly through short 
and properly graded drains, into a receptacle, which shall hold them 
temporarily and harmlessly when they are fresh, until they attain a 
volume, which, when suddenly released, will have the effect of charging 
the main drain of the house, more or less full bore, throughout the whole 
or the greater part of its length. 

Mr. Shone has designed such an apparatus. This, which is called 
a " House-Sewage Ejector," will receive anything in the shape of sew- 
age proper, and permit what it receives to pass out of it freely. It i> 
perfectly automatic in its action. The tributary house-drains are mad< 
to converge to it, instead of converging, for instance, to a cesspool. 
The apparatus, Fig. i, is so shaped that whether it be empty or full it 
always forms a deep fresh sewage w£iter-seal or trap, to prevent any 
sewer-gas, which might be formed in the public sewer, into which it 
contents are automatically discharged, from passing through it into any 
of the tributary house-drains. The apparatus is well ventilated, it is 
self-cleansing, and would di-charge ten times a day, at a household yield- 
ing 300 gallons per day, into the sewage system of a city. 

The sanitary collection and propulsion of all domestic waste-fluids 
can be relied upon by aid of this apparatus. 

The mechanical appliances required in connection with the com- 
plete application of the Shone system consist of : 

1 st. " Hydraulic Sewage-Ejectors " fixed at the house. " H ydrauli 
Flushing Ejectors" fixed at the head of the 7-inch gravitation sewers. 

2d. "Pneumatic Sewage-Ejectors " fixed at as many stations within 
the area, district, ot city to be drained, as may be desirable. 

3d. Steam-engines and boilers, where water-power is unavailable, air- 
compressors and air-receivers ; these latter are fixed at one station, from 
which air-mains are connected to the various pneumatic ejector stations. 
The hydraulic and pneumatic ejectors are made of cast iron, of any 
capacity or shape. 

Figure 2 is a drawing of a pneumatic sewage ejector, showing how 
it receives the sewage through the inlet-pipe, and how it ejects it again 
through the outlet-pipe, into what is called a sealed iron sew main. 

These ejectors are, by preference, put in duplicate, at each pneumatic 
station. The gravitation sewers carry the sewage to the inlet-pipe, down 
which it flows into and fills the ejector. On this inlet-pipe there is a 



IO 




TRAP 



SIPHON CUTLET TRAPPED 



OUTLET INTO MOUSE D«A*N 



FlGUR] I 




I MILE — 




Figure 2 



I 2 



lignum vitae ball-valve, which, by the inflowing action of the sewage, is 
lifted off its seat, and thereby permits the sewage to enter the ejector. 
There is a corresponding valve of the same material and make on the 
.>utlet-pipe. When the ejector is full the compressed air is automatic- 
ally admitted into it, and that same instant the sewage in the ejector 
tries to escape back to the gravitation sewers whence it came ; but the 
ball-valve on the inlet-pipe falls on its seat to prevent it. The sewage, 
therefore, can only escape from the ejector via the outlet pipe, which it 
does by lifting and consequently passing the ball-valve on that pipe. 
When the whole charge of the ejector has thus escaped, the automatic 
gear, which is extremely simple and strong, is instantly set in motion, 
and the result is that the compressed air rushing into and ejecting the 
sewage, is stopped from entering the ejector any longer, and simultane- 
ously the exhaust port of the automatic cylinder is opened to permit 
the compressed air, that had ejected the first charge of sewage out of 
the ejector, to escape into the atmosphere direct, or into the gravitation 
ewers to aid in their ventilation. This is of advantage, as it has been 
Tiown by Professor Tyndall that compressed air destroys organic germs. 
The moment this happens, the ejected sewage in the outlet-pipe tries, as 
it were, to get back into the ejector, but it is prevented from doing so 
by the ball- valve inserted in it. The sewage in the inlet- pipe, however, 
the moment the pressure within the ejector is reduced below the pres- 
sure which is due to a column of water, corresponding to the drop there 
is between the surface of the sewage at the top of the inlet-pipe, and 
the surface of the sewage within the ejector (when this latter has been 
emptied of its charge) begins to descend and to rush into the ejector, 
past the inlet ball-valve, at such a velocity as will insure the seat of the 
valve and its chamber being kept in a self-cleansing condition. The 
sewage will continue to flow down the inlet-pipe, as fast as it finds its 
way to the pneumatic ejector stations, until the ejector is filled, when the 
inflowing action will be arrested as before, to permit of the ejector being 
again emptied ; and so the operation of filling and emptying will go on 
from minute to minute, and from hour to hour, until the day's work is 

done. 

The illustration shows how these ejectors are connected with the 

gravitation sewers which fill them, and it also shows how they are 
coupled up to a sealed iron sewage main. Any number of ejectors may 
be coupled up in this way to one sewage main common to all, however 
near to, or distant from, each other they may be. As the quantity of 
sewage ejected increases at each station, so will the diameter of the 
sewage main be increased accordingly. But this sewage mam will 
convey the sewage out of the city, to any desired point of outfall, on the 



T 3 



same principle that the water-supplies are brought into the city — that is, 
under pressure ; and what is most important of all, the sewage so con- 
veyed, like the potable water so conveyed, will not offend the olfactory 
organs of the public who walk over them. Once the sewage is ejected 
into this sewage main, it cannot escape therefrom, neither can the de- 
composing agent, the atmosphere, get at it till it reaches the outlet end 
of it. But as the sewage reaches the pneumatic ejector when it is fresh 
and harmless, it follows that it must arrive at the outlet in that condi- 
tion, however far distant it may be from the various ejector stations. 

These sewage-receiving and sewage-discharging ejectors, distrib- 
uted about the city, in the manner described above, are connected by 
means of small iron air-pipes with the air-compressing station, very 
much in the same way as the gaseliers in our houses are connected with 

the gas-works. 

The ejectors, too, work noiselessly out of sight, as they are fixed in 
a small manhole-like chamber under the street, and being thus placed 
their sites will cost nothing to the municipality. 

The power of the engines and boilers, of course, depends upon the 
density to which the air has to be compressed in each case. A few ex- 
amples are given in the following table (see page 14) of the engines, 
boilers, and air-compressors, etc., employed on executed works. 

Gas-engines can be advantageously employed for compressing air, 
when the volume of sewage, and the height to which it has to be lifted, 
is not great. Atkinson's differential 4-horse-power gas-engines are 
used at the Houses of Parliament. 

The air-compressing station may be erected in a city, on any site 
which can be bought cheaply, or which, for other reasons, m, be con- 
sidered the most suitable for the purpose. Compressed air, unlike 
water, does not consume great p< er in transmission. On the con- 
trary, the power absorbed in its transmission to great distances, so long 
as the velocity is not excessive, is known to be inappreciable. In prac- 
tice it is found best to adjust the sizes of the pipes to admit the com- 
pressed air travelling at the velocity of twenty feet per second. 

The power of compressed air has long since been known, but it is 
only of late years that its application has been extensive. At first the 
engines used for compressing it were of the rudest type, resulting in 
giving the power a bad name, on account of the expense attending its 
compression and utilization. Now, however, the science and practice 
connected with the production and utilization of compressed air as a 
motive power are well known. The writer would point out that the 



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way in which compressed-air power is utilized on the Shone system, en- 
ables its users to get the highest possible efficiency out of it. 

On the Shone system, the air, before it does the work of which it 
is capable, does not actuate an executive engine, thereby losing the 
air and power necessary to actuate such executive engine or pump, 
which varies from twenty-five to fifty per cent., according to the size 
and make of the executive engine, but it is wholly employed in doing 
the work required of it. Instead of pushing the piston of an executive 
engine or pump backwards and forwards, when it is admitted into the 
ejectors, it pushes the sewage itself out. The sewage in the ejector 
thus becomes a piston, which is driven downwards by pneumatic press- 
ure out of the ejector. When the full charge of sewage has been 
ejected, the charge of compressed air, which has ejected it, escapes into 
the atmosphere or into the sewers, through the exhaust ports of the 

automatic gear. 

The total percentage of the volume of compressed air which is lost 
in actuating the automatic gear, connected with the ejector, and which 
is lost in clearance and otherwise, is a mere bagatelle, and need never 
exceed, in ejectors of 200 gallons capacity and upwards, one per 
cent. The compressed air being applied direct on to the surface of 
the fluid, its whole power is thus exerted, and that without any appre- 
ciable loss from friction due to the expulsive action of the ejector 
itself. The degree of economy realizable by the use of the ejectors 
increases as the number of stations at which it is desired to pump 
increase, because it matters not how numerous and widely apart the 
ejectors may be, they can be operated from one air-compressing station 
with the same facility and economy practically, and with the same un- 
erring certainty of automatic action, as if there was only one ejector- 
station, and that close to the air-compressing plant. 

Besides being able upon the Shone system, to eject sewage up to a 
lift of, say, fifty feet, at one pumping-station, as economically as if a 
really satisfactorily economical pump was employed to do the same 
amount of work ; as already intimated, sewage can also be ejected at 
ever so many different pumping points, however far or distant they 
may be from one another. The bulk of the sewage would this way be 
diverted to the outfall, at comparatively short lifts, instead of the whole 
gravitating down to the lowest point, and there raised the maximum 
lift. In order to carry out this division of districts, the lifts might pos- 
sibly be unequal, and in such cases reducing-valves would be employed 
to lower the pressures required for the low lifts. 

When it becomes desirable to raise the sewage from the lowest to 
the highest level at one lift, it will be necessary to compress the air in 



i6 

the first instance, to the maximum density required for the highest lift, 
and allow it to expand again to the volume corresponding to the press- 
ure due to the next lift, and so on, as suggested above. The best 
plan, however, is to try to divide the maximum lift into a number of as 
nearly as possible equal stages, say of fifty or sixty feet lifts, and to 
compress the air to the density required for one lift, the sewage being 
ejected successively through the several stages. At first sight this 
might appear to involve a loss of economy, but it is not so, as in point 
of fact there is a considerable gain in dividing up the lifts in the 

manner indicated. 

To provide uniformity of working, air-receivers are employed, the 
air being compressed to a slightly greater pressure than is necessary to 
raise the sewage, but in some cases the mains themselves afford quite 

enough storage capacity. 

The air-compressors, as well as engines and boilers, are always 

provided in duplicate. 

The writer may here add that the corporation of Birmingham (one of 
England's chief manufacturing towns) has approved of, and Parliament 
has sanctioned the formation of, a compressed-air motive-power com- 
pany for supplying compressed air to users of steam in Birmingham. 
At the first installation it is proposed to supply compressed air enough 
to work engines, which will indicate, in the aggregate 5,000 horse- 
power. This project has been thoroughly investigated by eminent and 
competent engineers, and the result of their investigations prove that 
the present steam-users in Birmingham, will effect a great saving by 
using the compressed air, supplied at rates, which will insure a hand- 
some financial success to the company. 

Competent engineers have designated the Shone system "the 
system of the future." At present it is in its infancy, but already it is 
in operation at eighteen different towns and districts in the United 
Kingdom and abroad, in each of which it has given entire satisfaction. 
The schemes that have been submitted, and approved of, by the sanitary 
authorities in the United Kingdom and abroad, and which have been 
adopted, and wholly or partially executed, will involve when completed 
an expenditure of nearly half a million pounds sterling. 

In addition to towns like Henley and Beaumaris, which have 
adopted the system in its entirety, the writer desires to point out how 
it may be advantageously applied as an auxiliary to the ordinary gravi- 
tation system of city drainage. 

At Eastbourne "ejectors" are employed to drive out to sea, at the 
highest possible state of the tide, the sewage of a population fluctuating 



I 



17 

between 26,000 and 80,000, so that the sewers throughout the towns are 
kept free from any accumulation or impounding of the sewage, which 
under the old gravitation system was the case, where any portion of the 
sewers were tide-locked. The authorities at this important watering 
place, were so satisfied with the working of the ejectors at the main 
station, that they put a second station, two miles distant from the first, 
in, the now, most fashionable quarter of the town, in a spot that had re- 
mained unbuilt upon because of the difficulty of drainage by the ordi- 
nary methods. Recently they have put down a third station, in another 
part of the town, 1 J4 mites distant from the air-compressing station, and 
the whole of the ejectors are worked from a single compressing station 

with equal facility. 

. At Warrington, the system is applied to a low-lying portion of the 
town to lift the sewage into the existing gravitation sewers. The cor- 
poration subsequently put down other ejectors, for the removal of 'ex- 
creta' and 'pail contents' from their several depots in the town, to their 

central works. 

Again at Southampton the sewage flows into a reservoir, where it is 
chemically treated, and ejectors are employed, first to discharge th< 
effluent water into the sea, regardless of the state of the tid< md after- 
wards the sludge into a depot, where it is further treated with ashe ind 
road sweepings, the compound having a ready sale in the district. 

At the Royal Courts of Justice Chambers, I ndon, ejectors are en 
ployed to lift the sewage from the crypts into the Metropolitan sew« r 27 
feet above them. The sewage of the new business premises r ently 
constructed in old Broad Street. London, at a cost of ,£300,000, is 
raised by an ejector 20 feet into the Metropolitan sewer. The ejector 
is placed in the floor of a wine cellar, and supplied with air b 1 West- 
inghouse compressor. By this system the value of land in a city 1 on- 
siderably increased, as it enables deep basements to be properlj drain 1. 
These are a few only of the many ways in which the m can be em- 

ployed otherwise than in its entirety. 

Putting efficiency, which is the true value of sanitary works, aside 
for a moment, the writer would point out that in places, where it is 
necessary to raise the sewage collected at one outfall, the machinery 
necessary to do this (with rising or gravitation outfall) is, as rosily as the 
machinery and sewage main employed in the Shone system, and the 
can be no question as to the relative cost of small stoneware pipes, laid 
in shallow trenches, and large and deep sewers, in laving which the 
amount expended on pumping alone is often very serious. 

W ith regard to annual charges, these have been proved in pi tice 
to be less than the maintenance of one sewage-pumping station, together 



i8 

with staff required to look after the flushing arrangements which large 

and flat sewers require. 

It would not be much criterion to give the actual cost of works 
executed upon the Shone system, as the value of labor and materials 
varies so much in different countries. However, for the sake of showing 
the economy in first cost, and annual charges, of the Shone system as 
compared with the ordinary gravitation system, the writer gives the fol- 
lowing particulars of the cost of the Shone system as executed at a town 
in England, and also the estimated cost of a gravitation and direct 
pumping scheme, prepared and estimated for, by an engineer of emi- 
nence. It may be added, that, in this as well as two other cases, the 
Shone system was adopted, after schemes on the gravitation system had 
been prepared and paid for by the authorities. 




Remarks 



£14,890 



7"™ finn fnin ifllZ These estimates include everything except land. 1 he Shone sys- 
X,*y,^"-'|X>J AW aw tem lllts the sewage ^o feet and delivers it from 5 separate 

ejector stations on to land 2 miles from the town. The scheme 
in the old system was to lift the sewage 40 feet only.and to deliver 
it on to land close to the town, and therefore on to more valuable 
land. Owing to the level of the subsoil water throughout the 
district, and the depths at which the sewers were proposed to be 
laid on the old system, it may be taken for granted that the work 
could not have been carried out for the estimated amount. 



The following is a summary of the advantages claimed for the 
Shone Hydro-Pneumatic System of Sewerage, which is patented in 
Great Britain, America, France, Germany and Italy : 

1st. Good and self-cleansing gradients can always be adopted, irre- 
spective of the configuration of the natural surface. This is of paramount 
importance at health resorts. 

2d. Impounding of sewage is altogether prevented — decomposition 
of sewage therefore never takes place — dangerous sewer-gases are not 
generated, and therefore the objections arising from open ventilators 
do not arise. 



3d. In tide-locked towns, the ejectors force the sewage into either 
river or sea under even' condition of tide. 



19 

4th. Small sewers and drain-pipes only are required, whereby the 
first outlay is considerably reduced, and the saving thus secured morethan 
compensates for the annual expenses for working the ejectors. 

5th. It is not necessary to take the future growth of any town into 
consideration, as any increase in population can be provided for, when 
it arises, by putting down additional ejectors as they are required. 

6th. Not being tied to any one site for an air-compressing station, 
it can be erected anywhere, on any cheap site, and from thence the 
compressed air conveyed miles away (if necessary) in small pipes to the 
ejectors. 

7th. No expenses for ejector sites — as the ejectors can be placed 
under a roadway — they require no attention, and give off neither smoke 
nor smell. 

8th. The lifting of the sewage at the different ejector stations to 
any required elevation is effected automatically — no stoker or atten- 
dants are required — there is no machinery likely to get out of order 
and no consumption of the compressed air, unless the ejector is full and 
requires emptying. 

9th. The advantage of being able, if necessary, to store up the 
compressed air in receivers, sufficient for many hours' consumption at 
the ejectors, so that the engines need only work a limited time, and at 
intervals, to replenish the receivers. 

10th. The fact that the " Shone " appliances can play their part in 
ameliorating and supplementing existing sewerage arrangements, with- 
out, in the majority of cases, necessitating a reconstruction of the works, 
need only to be understood to be appreciated as it is at Eastbourne, 
Warrington, Southampton, Winchester, and other places. 

\ The writer, as representative in the United States of Messrs. 

Hughes & Lancaster, the sole licensees in Great Britain and abroad, of 
the "Shone patents," will be happy to furnish any further information 
upon being communicated with at the undermentioned address. 



URBAN H, BR00GHT0N 
ASSOC. MJNST.CE. 

67-240 La Saile Street, 

. CHICAGO.